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Conference

Conference on Scientific Computing 

About: Conference on Scientific Computing is an academic conference. The conference publishes majorly in the area(s): Expert system & Software system. Over the lifetime, 1277 publications have been published by the conference receiving 8001 citations.


Papers
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Book ChapterDOI
08 Dec 1997
TL;DR: The Macroscopic Electrostatics with Atomic Detail (MEAD) suite as discussed by the authors is a set of object-oriented classes and programs in C++ that implement molecular electrostatic models.
Abstract: We have developed a set of object-oriented classes and programs in C++ that implement molecular electrostatic models that can be described by the term, Macroscopic Electrostatics with Atomic Detail (MEAD). In the course of developing the MEAD suite, we have shifted from a class hierarchy rooted in atoms and molecules, to a system in which the top-level classes are the electrostatic potential and the entities that determine the potential in the equations of electrostatics: the charge distribution, the dielectric environment and the electrolyte environment. Atoms and molecules are then seen as objects giving rise to, or occurring as subclasses of, charge distributions, dielectric environments, etc. This shift in focus from the physical objects (molecules) to the more abstract objects that appear in the underlying physics has facilitated the development of alternative approximation schemes and numerical methods through subclassing. It also provides a natural way of writing high level programs in terms of potentials and distributions. Some of the newer elements of C++, such as templates and RTTI, have proven useful to solve multi-method and default method problems. MEAD is distributed as free software.

295 citations

Journal ArticleDOI
01 May 2007
TL;DR: This work analyzes a class of large time-stepping methods for the Cahn-Hilliard equation discretized by Fourier spectral method in space and semi-implicit schemes in time and investigates the stability and convergence properties based on an energy approach.
Abstract: In this work, we will analyze a class of large time-stepping methods for the Cahn-Hilliard equation. The equation is discretized by Fourier spectral method in space and semi-implicit schemes in time. For first-order semi-implicit scheme, the stability and convergence properties are investigated based on an energy approach. Here stability means that the decay of energy is preserved. The numerical experiments are used to demonstrate the effectiveness of the large time-stepping approaches.

208 citations

Proceedings ArticleDOI
01 Feb 1988
TL;DR: This paper augments the relational database, with neighborhood systems, so the database can answer a fuzzy query, and defines directly the meaning of “very close neighborhood”.
Abstract: Queries in database can be classified roughly into two types: specific targets and fuzzy targets. Many queries are in effect fuzzy targets, however, because of lacking the supports, the user has been emulating them with specific targets by retiring a query repeatedly with minor changes. In this paper, we augment the relational database, with neighborhood systems, so the database can answer a fuzzy query. There have been many works to combine relational databases and fuzzy theory. Bucklles and Petry replaced attributes values by sets of values. Zemankova-Leech, Kandel, and Zviell used fuzzy logic. The formalism of present work is quite general, it allows numerical or nonnumerical measurements of fuzziness in relational databases. The fuzzy theory present here is quite different from the usual theory. Our basic assumption here is that: the data are not fuzzy, the queries are.Motro [Motr86] introduced the notion of distance into the relational databases. From that he can, then, define the notion of “close-ness” and develop goal queries. Though “distance” is a useful concept, yet very often the quantification of it is meaningless or extremely difficult. For example, “very close”, “very far” are meaningful concept of distance, yet there is no practical way to quantity them for all occasions. Our approach here is more direct, we define directly the meaning of “very close neighborhood”. Using the concept of neighborhoods is not very original, in fact, in the theory of topological spaces [Dugu66], mathematician has been using the “neighborhood system” to study the phenomena of “close-ness”. In the territory of fuzzy queries, the notion of “neighborhood” captures the essence of the qualitative information of “close-ness” better than the brute-force-quantified information (distance). A “fuzzy” neighborhood is a qualitative measure of fuzziness.On the surface, it seems a very complicated procedure to define a neighborhood for each value in the attribute. In fact, if we use the characteristic function (membership function) to define a subset, then the defining procedure is merely another type of distance function (non-measure distance or symbolic distance). Now, to define the neighborhood system one can simply re-entered the third column of the relation with linguistic values: “very close”, “close”, “far”. Note that there is a “greater than” relation among these linguistic values. In mathematical terms, they forms a lattice [Jaco60]. For technical reason, we require the values in third column be elements of a lattice. Note that real number is a lattice, so we get Motro's results back.

185 citations

Proceedings ArticleDOI
21 Feb 1989
TL;DR: A family of trees is constructed to demonstrate that for each k, some trees need k colors to achieve the minimum sum, and it is proved that this family gives the smallest trees with this property.
Abstract: We introduce the new concept of the chromatic sum of a graph G, the smallest possible total among all proper colorings of G using natural numbers. We show that computing the chromatic sum for arbitrary graphs is an NP-complete problem. Indeed, a polynomial algorithm for the chromatic sum would be easily modified to compute the chromatic number. Even for trees the chromatic sum is far from trivial. We construct a family of trees to demonstrate that for each k, some trees need k colors to achieve the minimum sum. In fact, we prove that our family gives the smallest trees with this property. Moreover, we show that asymptotically, for each value of k, almost all trees require more than k colors. Finally, we present a linear algorithm for computing the chromatic sum of an arbitrary tree.

158 citations

Proceedings Article
01 Jan 2010
TL;DR: PDELAB considerably simplifies the implementation of discretization schemes for systems of partial differential equations by setting up global functions and operators from a simple element-local description.
Abstract: In this paper we describe PDELAB, an extensible C++ template library for finite element methods based on the Distributed and Unified Numerics Environment (DUNE). PDELAB considerably simplifies the implementation of discretization schemes for systems of partial differential equations by setting up global functions and operators from a simple element-local description. A general concept for incorporation of constraints eases the implementation of essential boundary conditions, hanging nodes and varying polynomial degree. The underlying DUNE software framework provides parallelization and dimension-independence.

148 citations

Performance
Metrics
No. of papers from the Conference in previous years
YearPapers
202013
20193
201837
20171
201614
20152